1. Field of the Invention
The described technology relates generally to a rechargeable battery where the case may be bent in a longitudinal compression condition.
2. Description of the Related Art
Unlike a primary battery, a rechargeable battery (i.e., a secondary battery) can be repeatedly recharged and discharged. Typical rechargeable batteries include a nickel-hydrogen battery, a lithium battery, a lithium ion battery, and the like. The rechargeable battery is manufactured in the form of a pack, and is commonly employed for mobile electronic devices such as cellular phones, notebook computers, and camcorders.
The rechargeable battery includes a jelly roll type of electrode assembly formed by winding a positive electrode and a negative electrode with a separator interposed therebetween in a stacked manner, a case receiving the electrode assembly along with electrolyte therein, and a cap assembly positioned on an upper opening of the case.
For example, the case is made of aluminum or an aluminum alloy, and has a cylindrical or angular shape. The case is compress-deformed due to pressure applied to a narrow side of the case in a perpendicular direction with respect to the up and down direction. That is, a lower wide side of the case is folded under in the longitudinal compression condition.
Under the longitudinal compression condition, a crack may be formed in the case when the side of the case is bent, and then the crack sequentially penetrates a negative electrode and a positive electrode of the electrode assembly, thereby causing a short-circuit between the negative electrode and the positive electrode in the electrode assembly. Due to such an internal short-circuit, the rechargeable battery may be ignited or exploded.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.